Just got my last FOI request back from the DHSC about the PCR tests they are using Some really interesting comments in it such as:
– do the tests you are using detect only “covid-19” as stated in the Coronavirus legislation: “coronavirus” means severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)? The test is for SARS-CoV-2 RNA. – or does it show positive to all the coronavirus family of viruses? Just SARS-CoV-2 RNA. – supply the justification that a “positive” test means the person is suffering from the virus as is a danger to the public and must be isolated. SARS-CoV-2 RNA means the RNA is present in that sample at that point in time. It does not mean that the patient has the novel coronavirus (COVID-19). my highlighting so no justification provided for isolating people regardless if their test is positive. Patients can have SARS-CoV-2 RNA before onset of illness, during the illness and after resolution of symptoms (all variable periods). The result has to be taken into context of symptoms present. They also provide a link to a document by Health Technology Wales which in answer to this question: – the official policy/guidance from DHSC to the various bodies who are following the above policy. I can confirm that the Department holds information relevant to your request. As the information held by the Department is in the public domain, we will under Section 21 of the FOI Act (information accessible to the applicant by other means) refer you to the published source, a summary of evidence on the accuracy of the test,
It does include a few gems such as:
We identified 39 individual studies and one pooled analysis reporting outcomes including diagnostic accuracy, detection rates and the time taken to obtain test results. We carried out quality assessment of the studies and judged the majority to be at risk of bias in one or more aspect of their design or conduct, which means their results may not be reliable. So not too accurate then these studies?
Some studies did not include methods of confirmatory/differential diagnosis to validate the test results obtained (e.g. the proportion of likely false positive and negative results). A pooled analysis estimated the sensitivity of an initial RT-PCR test result to be 89%, using results of repeated RT-PCR as the reference standard. So does this mean that there is an estimated 11% false result?
There are important gaps in the available evidence on the effectiveness of tests for the presence of SARS-CoV-2. Studies of virus testing in asymptomatic patients, or in specific populations such as healthcare workers are limited in number and there is no evidence on the validated diagnostic performance of the tests beyond their use in the hospital setting. So pretty useless then?
a true assessment of the accuracy of RT-PCR test results is very challenging, and using these RT-PCR for validation mean the same issues apply to the results of antibody tests studied in this way. so the test has lots of problems with accuracy and the antibody test cannot be used for doublechecking the results due to these inaccuracies? again not too useful a test if it has so many accuracy problems?
At least they have answered truthfully and reading between the lines I come up with “it’s all bollocks and we cannot accurately test for it to tell if anyone has it”.
Great stuff thanks @Awkward Git. I suspect there may be some truth modification happening in the second answer ('Just' SARS CoV2 RNA) because many sources (Dr Kaufmann, Australian dept of health to name two that spring to mind) have said that the RNA detected in the test is common to other coronviruses too, if I am correct it only checks for a single strand of RNA (of many, I assume, in the virus). Am happy to be corrected of course (I'm going through the linked document, but it's 76 pages!!!) Thanks again.